Wi-Fi Direct Network is the network capable of enabling Wi-Fi devices to be connected to each other by peer-to-peer without participating in a home network, an office network or a hotspot network, and was proposed by Wi-Fi Alliance (hereinafter abbreviated WFA).
While a vehicle is driven, if abnormality occurs in the driven vehicle, it is necessary to notify such an abnormal state to drivers of other vehicles. If one of the drivers of the other vehicles recognizes the abnormal state, as the corresponding driver performs defensive driving, the possibility of accident occurrence can be lowered and the damage caused by an occurring accident can be reduced.
Currently, a separate communication method capable of exchanging information between vehicles fails to exist. Conventionally, abnormal signals may be exchanged by applying various kinds of wireless communication methods existing previously.
However, in case that an abnormal signal is transmitted between vehicles using a wireless communication, the signal transmission can be performed after establishing a session for the wireless communication in advance. Although wireless communication systems may differ from each other in consumed time, they are similarly required to consume a considerable time to establish the session.
Thus, since an inter-vehicle transmission of an abnormal signal needs to be performed as a transmission of an emergency signal as quickly as possible, the demand for researching & developing such an inter-vehicle transmission of an abnormal signal is increasingly rising.